PROJECT SUMMARY/ABSTRACT- Project 2 Our long-term goal is to ameliorate the debilitating consequences of age-related hearing loss- ARHL (presbycusis). ARHL interferes with effective communication by reducing the audibility of sounds, degrading the intelligibility of speech in quiet and noisy backgrounds. The overall objective of this research is to identify and understand effective methods for mitigating these aspects of ARHL. Project 2 employs behavioral experiments with animal models toward this end, integrating the findings with those of sister projects on this Program Project grant. The central hypothesis is that targeted therapeutic interventions will induce beneficial changes in the ear and brain- central auditory system (identified with behavioral tests), leading to amelioration of chronic deficits that define presbycusis. In conjunction with sister projects, we will identify the behavioral, perceptual, neurophysiological, and molecular bases of ARHL and how they are affected by our biotherapeutic interventions. Specific Aim 1 focuses on the potential to use aldosterone supplementation to improve inner ear and brain function. Specific Aim 2 uses targeted special sounds, called augmented acoustic environments (AAEs) to improve processing of speech timing features and hearing in background noise. Specific Aim 3 evaluates a new intervention, transcranial magnetic stimulation, for the treatment of maladaptive plasticity in the aged central auditory system following peripheral hearing loss. The comprehensive framework proposed here is the first to our knowledge combining basic and applied methods to address amelioration of AHRL in a manner that allows rapid translation of research findings to clinical practice ? the foremost goal of NIA and NIH at large.